iPhone 3.0 - No WiFi.

So, ever since I upgraded my 3G to 3.0 I've literally had no wifi, nothing comes up in the wifi menu and I've tried everything that has been said about the issue. I've reset network settings etc and still nothing, most people's phones can at least see networks, but I'm yet to.

Although my G3 iPhone detects a wifi network when I am home, as soon as I go on-line the icon disappears and I am then on the normal cellular provider network. I have been checking forums for weeks now and someone suggested switching off security settings on my router.
This I did and, hey presto, wifi works perfectly. When I restore the security settings on my router, wifi drops immediately. At least I know that the iPhone is working. I have a Netgear MR814v2 router.
I hope this also helps someone else

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